The invention relates generally to radiation shielding systems and more particularly to a modular type reactor head shielding system designed to be temporarily assembled around a reactor head such as during refueling operations. The system employs a frame or track around the periphery of the reactor head to which shielding pads can be quickly and easily attached while providing maximum protection to workmen.
In nuclear power plants, the reactor heads are removed during refueling operations. The reactor head typically is situated in a concrete type well and is removed from the well during the refueling operation. During these operations it would be desirable to have the reactor head shielded so that workers are not exposed to radiation from the reactor head.
Each worker typically is attired in radiation protective clothing; however, each reactor head typically is secured by a large number of stud bolts around the top of the reactor which must be removed resulting in exposure to the workers.
Attempts to reduce this exposure have been made such as by hanging or placing lead shielding such as individual bags, around the reactor head. These non-integrated systems have several disadvantages including exposure between the single layer of bags, no system to secure the bags to the reactor head and possible damage to the reactor head by the jury rigged systems.
With the prior art shielding systems it was also not desirable to hang the bags around the reactor head on a frame or other means since it would be preferable to move the shielding with the reactor head when it is removed to refuel the reactor. Further, the work space or well in which the reactor head is situated does not allow a large amount of clearance between the workers, the well wall and the reactor head.
Finally, with the prior art systems there is the problem of gaining access to any particular point on the reactor head while the system is in place. Any work on the reactor head required a complete disassembly of at least a portion of the shielding system and removal of the shielding from that area.